The present invention relates to a new and improved construction of a solar radiation collector for generating useful heat in a fluid medium, in particular a liquid.
Generally speaking, the solar radiation collector--also referred to in the art as a solar collector--of the present invention is of the type comprising a substantially horizontal infeed or inflow line for the liquid which cooperates with an outfeed or outflow line for the heated liquid, the outfeed line being located essentially parallel to the infeed line and at a higher elevation relative thereto. A heating device serves to heat the incoming liquid and incorporates mutually spaced, radiation absorbing tubes or pipes which interconnect the infeed and outfeed lines or conduits. The tubes each have a lengthwise extending axis which coincides with the focusing axis of an associated mirror or reflector which may be in the form of a substantially parabolic cylindrical mirror. All of these mirrors or reflectors are rotatably driven about their focusing axis, so as to be able to focus at any time the incident solar radiation upon the associated tube and to thus convey the heated liquid in the form of a convection flow into the outfeed line. The heating device is mounted as a unit within a hollow compartment which is closed at all sides. The hollow compartment has a front wall structured as a window for the extensively uninterrupted through-passage of the solar radiation, and its longitudinal and transverse walls as well as its rear closure wall are formed of thermally insulating material.
Equipment of this type is generally known, for instance from a combination of the French patent application No. 2,269,038, the German patent publication No. 231,294 and U.S. Pat. No. 2,907,318. Yet, manufacture of such equipment is however not optimally economical, since such equipment construction does not fully exploit the possibility of optimally utilizing plastics and/or foam plastics. In particular, the liquid lines or conduits and the thermally insulating walls, are designed and installed independently of one another.